基于延迟着色技术的大场景反走样渲染架构设计

Designing Anti-aliasing Rendering Structure for Large Scenes Based on Deferred Shading

为解决飞行仿真领域其视景系统对逼真、复杂场景渲染质量要求高的问题,提出基于延迟着色技术的大场景反走样渲染架构以实现全球地景及场景特效的真实感渲染,达到飞行训练的效果。本渲染架构主要解决延迟着色技术与硬件反走样技术——覆盖采样反走样(CSAA)不兼容的问题,在延迟阶段生成带CSAA反走样的多渲染目标缓存(G-Buffer),在着色阶段通过记录在特定通道中的透明度蒙版信息进行几何体边缘恢复以进行最终的光照计算;对不同绘制组件开启不同等级的反走样等级以达到效果与效率的平衡,并利用类层次细节(LOD)模型构建技术及标记重要边界信息进行后处理等加强反走样效果。采用本渲染架构开发的视景系统,从实际训练及实验所得到的数据与效果表现上决定不同负载组件最终的采样倍数,这样系统的实时性高(>60fps),能达到飞行模拟视景对渲染效率的要求,减少延迟与卡顿;同时该框架反走样效果好于亚像素还原反走样(SRAA)算法,从而视景系统能达到性能与画质的最佳组合。通过实际训练与飞行模拟专家鉴定,基于该框架系统的视景系统能达到飞行仿真训练的目的。

In order to meet the high requirements of realistic and complex scene rendering in the field of visual flight simulation,this paper proposed an anti-aliasing rendering structure for large scenes based on deferred shading,to achieve realistic rendering for a global landscape and all kinds of effects.The incompatible problems that built-in hardware anti-aliasing CSAA did not work with deferred shading were mainly solved by our rendering architecture,which depended on generating a multi-render target G-Buffer with CSAA anti-aliasing in the deferred phase and performing the final lighting calculation by recovering the geometry edge through the transparency mask information recorded in a particular channel during the shading phase.At the same time,different rendering components were set different levels of anti-aliasing to balance between efficiency and effectiveness.To improve anti-aliasing effects,the LOD model-building technology was used and the important post-process boundary information were marked.Owing to the final sampling multiples of different load components form actual training and the data and effect performance of the experiment,the visual system developed by rendering architecture had reached high real-time performance.It usually met over 60 fps,which greatly reduced latency and blocking.Meanwhile,the anti-aliasing effect was better than SRAA algorithm.Therefore,the visual system could achieve the best combination of performance and quality.It can achieve the purpose of flight simulation training identificated by training experts.